#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>

void waiter(int wfd)
{
    const char* str="hellow father,I am child.";
    char buffer[128];
    int cnt=0;
    pid_t pid=getpid();
    while(1)
    {
        snprintf(buffer,sizeof(buffer),"message:%s,pid:%d,count:%d\n",str,pid,cnt);
        write(wfd,buffer,strlen(buffer));
        cnt++;
        sleep(1);
    }
}

void reader(int rfd)
{
    char buffer[1024];
    while(1)
    {
        ssize_t n=read(rfd,buffer,sizeof(buffer)-1);
        (void)n;
        printf("father get a message:%s",buffer);;
    }
}

int main()
{
    int pipefd[2];
    int n=pipe(pipefd);
    if(n<0)
    {
        return 1;
    }
    printf("pipefd[0]:%d,pipefd[1]:%d\n",pipefd[0]/*read*/,pipefd[1]/*write*/);
    pid_t id=fork();
    if(id==0)
    {
        close(pipefd[0]);
        writer(pipefd[1]);
        exit(0);
    }
    close(pipefd[1]);
    reader(pipefd[0]);
    wait(NULL);
    return 0;
}